A female Forcipomyia biannulata was collected on 19 October 2022 on Long Key, Monroe County, Florida, USA, at the staff residences in Long Key State Park, in a carbon dioxide-baited light trap set for routine mosquito surveillance.  A single larval mite, Leptus sp., was attached to the ventral abdomen between segments three and four (Fig. 1).   Both the midge and the mite were mounted on microscope slides and sent to experts for verification of identifications.  Both specimens were deposited into the Florida State Collection of Arthropods (FSCA) (Midge: E5540-01-12022022-10603; Mite: E5543-01-12022022-10608).  Collections were made under authority of Florida Department of Environmental Protection Division of Parks and Recreation Permit Number 01242225.  A carbon dioxide-baited miniature light trap was suspended from a tree limb in the late afternoon of 18 October 2022 and retrieved the following morning.

Forcipomyia biannulata is known from the following Florida counties:  Brevard, Collier, Marion, Miami-Dade, Monroe, Polk, and Suwannee.  Although the midge was previously collected from the mainland portion of Monroe County, Florida, this record is the first from the Florida Keys.  This midge is an Afrotropical species, widespread throughout Africa and it also occurs in Canary Islands and Saharo-Arabian subregion of the Palaearctic; it has been introduced into Malaysia (Grogan et al. 2017).

This is not the first record of an association between Ceratopogonidae and Erythraeidae.  Bezzia bivittata (Coquillett) (Ceratopogonidae) was previously reported as a host for an erythraeid mite, also a Leptus species (Grogan 1982).  Erythraeid mites were attacking biting midges 70-80 million years ago (Poinar et al. 1993).  Erythraeids parasitize many orders of insects, although records from Diptera are not as common as from other orders of insects (Felska et al. 2018).  Two previous records of Leptus sp. From Monroe County, Florida, were from Lepidoptera (Hribar 2020, 2022).